The Energy Dispersion of the Chain Band in YBa2Cu3O6+y, and Its Effect on the Cu(2) NQR Frequency

Abstract

The energy dispersion of the chain band has been determined in the framework of the Hubbard model. The results are in agreement along the T-S and T-Y lines of the Brillouin zone with photoemission data. The amount of d3z2-r2 states is zero at y = 0 and increases to 10% at y = 1. The admixture is due to the hybridization of Cu(1) dy2−z2 states with Cu(2) d3z2-r2 states via apical oxygen. The effect of this admixture on the NQR Frequency of Cu(2) is discussed. © 1994, Verlag der Zeitschrift für Naturforschung. All rights reserved.